Process for polishing articles and a device for use therein



Jan. 17, 1950 E. G. WHITEHEAD 2,494,733

PROCESS FOR POLISHING ARTICLES f AND A DEVICE FOR USE THEREIN Filed June 25, 1946 NVENTCJ ERNEST GEORGE wnrruanp ATTORNEY Patented Jan. 17, 1950 PROCESS FOR POLISHING ARTICLES AND A DEVICE FOR USE THEREIN Ernest George Whitehead, Wolverhampton, England, assignor to The Wolverhampton Die- Casting. Company Limited, Wolverhampton,

, England Application June 25, 1946, Serial N 0. 679,226 In Great Britain March 15, 1946 4 claims. (01. 51 7) ....The invention has for its object to provide an improved process by which articles'may be auto" maticallyand ,efliciently polished, and to provide an: improved device for use therein .1 l

. ,Heretofore the polishing of small articles has .usually been. effected by holding such articles against a fabric, bob or mop rotated at a high speed and supplied with abrasive polishing material.

According i. to this'invention the articles are placed within a, drum containing small solid pieces of material and polishing material, the articles being mounted on a carrier within the drum, relativerotation being'provided between the drum and the carrier whereby the said small solid pieces of material are caused to rub against the articlesland, together with the polishing material, effect the polishing thereof, 1 The polishing material may be in the form of powder or compound, orthe said small solid pieces may have polishing material impregnated in them.

The small solid pieces of material may be composed of felt or other fabric. or of rubber, leather, papier-mache' or any other resilient material, or of shot or a combination of any of these. The inner periphery of the drum may be lined with resilient material, which may be some of the above named solid pieces of material held against the inner periphery by centrifugal force if the drum is rotated. The said inner periphery may, however, be permanently lined with resilient material, such as rubber, leather or fabric.

An example of the invention is described with reference to the accompanying drawings, of

which: Y

Figure 1 is a side elevation of the polishing device.

Figure 2 is a front end view thereof.

Figure 3 is a vertical section taken on the line 3, 3, of Figure l and looking in the direction of the arrow of that figure.

Figure 4 is a sectional plan view, the section being taken on the line 4, 4, of Figure 1.

Figure 5 is a detail in plan showing a simple means for driving the drum in opposite directions.

In these drawings, Ill indicates a main casting affording support to two bearings H, II, and a horizontal supporting bar 12, see Figure 1. Journalled in the bearings l l, I l, is a shaft 13 on which are keyed a belt pulley l4 and a hollow drum l5 which has a closed rear wall I6. Clamped on the bar I2 is an upwardly extending bracket ll having at its upper end a boss l8 in which is secured, by set screws IS, an arbor 2B which extends rearwardly into the drum i5 and is concentric therewith. On the rear end of the arbor 20 is keyed a circular carrier 2| which is located in the drum and has screwed into its periphery a set of radially extending arms 22.

Secured to the arms 22, by screws 23, are jigs 23a which 1101a the. articles 24 required. to be plate 29, this latter being secured against. the

flange 25 by wing nuts 36 screwed on the eye bolt The bracket I1 is clamped on the bar l2 by a sunk-headed screw 3| and a hand. clamping screw 32 ,both of which pass through clearance holes in a strap 33 and screw into tapped holes in the bracket ll.

In order to remove the carrier 2 I, with its arms 22, from the drum IS, the bolts 2? are disengaged from the cover plate and the hand screw 32 is slackened back. This permits of the bracket ll being slid back along the bar I 2 bringing with it the arbor 2|], the cover plate 29 and the carrier 2| with its arms 22. The articles 24 can then be detached and replaced. The drum is partially filled with small solid pieces of material 32, to gether with abrasive material.

When the articles have been fitted to the arms on the carrier, the latter inserted in the drum and the cover plate secured in position, the drum is driven at speed by applying power to the belt pulley M. The rotation of the drum, by imparting centrifugal force to the small solid pieces of material, causes a proportion of them to pack on the inner surface of the drum l5 and form a resilient layer which sweeps over the outer and side surfaces of the articles; or causes said small pieces to come in close proximity thereto; and the rotation causes other pieces of material passing between the said layer and the articles to rub against the articles. In either case the small solid pieces of material, and especially the abrasive material thereon, rapidly effect the polishing of the said outer surfaces and sides of the articles. The inner sides and the shanks of the articles are also polished by other of the small solid pieces of material revolving in orbits nearer to the axis of the drum.

It is beneficial to reverse the direction of rotation intermittently to equalise the polishing effect.

A simple mechanism for effecting reversal of the rotation may comprise a motor-driven shaft 4! having a pulley 4| keyed thereto and driving a countershaft 42 by a belt 43 and a pair of pulleys 44, and 45. Crossing the belt 43 as shown in full lines will obviously reverse the direction of rotation of the countershaft from that imparted by the straight belt shown in dot and dash lines. Countershaft 42 drives the pulley [4 by means of a belt 46 (shown fragmentarily) and pulley'41. Many other mechanisms, some fully automatic, for effecting reversal of the drum may be used within the scope of the appended claims.

The apparatus may be used horizontally or vertically or in intermediate positions. If the apparatus is horizontally disposed an aperture in the cover plate 29, allows for inserting and removing the polishing agents. The aperture is closed by a removable cover plate 35.

Having fully described my invention, what I claim and desire to secure by Letters Patent is:

1. In a device for polishing articles, said device comprising a hollow drum mounted for rotation from a source of power, a carrier held stationary within the drum, said carrier adapted to carry the articles to be polished, a wall closing one end of the drum, a removable cover closing the other end, small pieces of material and polishing material placed within the drum, and a lining of resilient material applied to the inner periphery of the drum, and means for operating the drum intermittently in reverse directions.

2. In a device for polishing materials, said device comprising a hollow drum, a fixed wall closing one end of said drum, an axially disposed shaft rigidly secured to said wall, fixed bearings in which said shaft is journalled, means for driving said shaft in reverse directions, a removable cover closing the other end of the drum, an axial and rigidly supported arbor extending through said cover, a carrier disposed axially within the drum 4 and carried by said arbor, said carrier adapted to carry the articles required to be polished and small solid pieces of material and polishing material placed within the drum.

3. A process for polishing articles, consisting in mounting the articles on a carrier within a drum, together with a mixture of resilient material and abrasive material, and rotating the drum at a speed suflicient to cause a portion of said mixture to pack on the inner periphery of the drum by centrifugal force and in closeproximity to the surface of said articles while other portions of said mixture pass between and in contact with said packed mixture and said articles, whereby to effect an abrasive polishing action thereof.

fl. A process for polishing articles, consisting in mounting the articles on a carrier within a closed drum, placing a mixture of resilient material and polishing material within the drum, rotating the drum at a speed high enough to cause a portion of said mixture to pack on the inner periphery of the drum by centrifugal force and in close proximity to the surface of said articles while other portions of said mixture pass between and in contact with said packed mixture and said articles, whereby to polish said articles.

ERNEST GEORGE WHI'I'EHEAD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name a Date 1,178,827 Spellman Apr. 11, 1916 1,352,598 Hart Sept. 14, 1920 1,890,443 Anstice et al Dec. 13, 1932 2,218,353 Gruenberg Oct; 15, 1940 2,425,640 -Pruitt et al. Aug. 12, 1947 

